primary root

American  

noun

Botany.

1. the first root produced by a germinating seed, developing from the radicle of the embryo.

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primary root Scientific  

1. The first root of a plant, originating in the embryo. In gymnosperms, eudicotyledons, and magnoliids, the primary root develops into the taproot. In monocotyledons, the primary root disintegrates as the lateral roots develop into a system of fibrous roots.

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Etymology

Origin of primary root

First recorded in 1885–90

Example Sentences

The root which first forms when the seed bursts is known as the primary root.

From Dry-Farming : a System of Agriculture for Countries under a Low Rainfall by Widtsoe, John Andreas

G, a germinating seed, × 2. r, the primary root.

From Elements of Structural and Systematic Botany For High Schools and Elementary College Courses by Campbell, Douglas Houghton

The single root of the commoner biennials is the primary root, or tap-root, which begins to thicken in the seedling.

From The Elements of Botany For Beginners and For Schools by Gray, Asa

These are all simple, that is, there is but one primary root.

From Outlines of Lessons in Botany, Part I; from Seed to Leaf by Newell, Jane H.

When the primary root grows more rapidly than the secondary roots, the so-called taproot, characteristic of lucerne, clover, and similar plants, is formed.

From Dry-Farming : a System of Agriculture for Countries under a Low Rainfall by Widtsoe, John Andreas